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Any technique that reduces the number of transfers/glassware required without sacrificing accuracy, is the way to go. Having said that. A little practice, and pouring right from the neck of the receiver flask into the vial can be done quite well.

I learned to pour into 1ml vials with the 13mm neck size(the narrow neck most pharm. vials use) directly from the neck of 100ml and 250ml volumetric flasks when I was doing a lot of quantitative analysis work. Saves a lot of time, and pipettes. You almost don't believe it can be done until someone shows you, though. Your first though is "Yea fuckin right, you want me to take that volumetric flask and pour into that tiny little 1ml vial without dumping the whole thing in my lap, yea fucking right."

JR, I don't know if this little gem has made it your way or not, but get a roll of teflon tape at the hardware store. It's a pure film of teflon used to help seal threads on water/gas pipes. Put a couple of wraps on the male part of your ground glass connection. BAM, no more leaking, no more stuck joints. And, if you find your filter membrane support leaking between the funnel and the lower fritted part, put a couple of wraps around the OUTSIDE of that joint after it has been assembled, the vacuum will do the rest to keep it sealed up. Be careful, you will be able to pull a much harder vacuum now that you have done these two things, you'll have to find something else to do with your time that you save filtering...

I need to write a book, Practical Lab Techniques and Beyond: An Introduction to Practical Chemistry and Lab Techniques for the Entrepreneur.

Any technique that reduces the number of transfers/glassware required without sacrificing accuracy, is the way to go. Having said that. A little practice, and pouring right from the neck of the receiver flask into the vial can be done quite well.

I learned to pour into 1ml vials with the 13mm neck size(the narrow neck most pharm. vials use) directly from the neck of 100ml and 250ml volumetric flasks when I was doing a lot of quantitative analysis work. Saves a lot of time, and pipettes. You almost don't believe it can be done until someone shows you, though. Your first though is "Yea fuckin right, you want me to take that volumetric flask and pour into that tiny little 1ml vial without dumping the whole thing in my lap, yea fucking right."

JR, I don't know if this little gem has made it your way or not, but get a roll of teflon tape at the hardware store. It's a pure film of teflon used to help seal threads on water/gas pipes. Put a couple of wraps on the male part of your ground glass connection. BAM, no more leaking, no more stuck joints. And, if you find your filter membrane support leaking between the funnel and the lower fritted part, put a couple of wraps around the OUTSIDE of that joint after it has been assembled, the vacuum will do the rest to keep it sealed up. Be careful, you will be able to pull a much harder vacuum now that you have done these two things, you'll have to find something else to do with your time that you save filtering...

I need to write a book, Practical Lab Techniques and Beyond: An Introduction to Practical Chemistry and Lab Techniques for the Entrepreneur.

It will help with the seal, but make sure none of your product comes in contact with it.

A little tip about the parafilm you may or may not know.

The parafilm is designed to be stretched before usage. (good god damn thing, that shit is expensive!)
One layer of parafilm will allow free air exchange (oxygen etc.)
Two layers of parafilm will NOT allow free air exchange.

Using the millipore stericup i found if i filter above 50deg C it eats the plastic in the top even with glass receiver, must be heat solvent combo and thats only using 2% 18%(no eo) just made it very very slightly cloudy.\

If im not mistaken, the plastic that couples and holds the filter on the stericup is wither HIPS or PES, neither suitable for use with the solvents we use.

Guys, NONE of the bottle top filters or syringe filters are really made to filter non-aquesous solutions. They were really designed for use with aqueous solutions like growth media and tissue culture growth fluids.

The only way to get this stuff to work without any problems, ever, is to be using all glass and either a nylon or PTFE membrane. PVDF will work almost all the time, but ANY other material plus BA, BB and oils like MCT or MIG and you're asking for trouble, not to mention using EO and Guaiacol.

These little differences are the whole difference between a high PIP batch and a smooth as silk batch.

Has anyone ever purged previously opened oil or solvent bottle in a vacuum chamber. Been a few months since using them and wonder how hydrophilic some of this stuff is?
The fact that 97% ethanol drops in percentage each time exposed to open atmosphere made me start thinking about this.

"Don't ask me if I take steroids and I won't tell you that you look like shit."

If im not mistaken, the plastic that couples and holds the filter on the stericup is wither HIPS or PES, neither suitable for use with the solvents we use.

Guys, NONE of the bottle top filters or syringe filters are really made to filter non-aquesous solutions. They were really designed for use with aqueous solutions like growth media and tissue culture growth fluids.

The only way to get this stuff to work without any problems, ever, is to be using all glass and either a nylon or PTFE membrane. PVDF will work almost all the time, but ANY other material plus BA, BB and oils like MCT or MIG and you're asking for trouble, not to mention using EO and Guaiacol.

These little differences are the whole difference between a high PIP batch and a smooth as silk batch.

Very new to this all apart from syringe filtering.
With glass can you get sterile filter membranes.

I presume with glass as well, filtering temp isnt such a worry and as you said harsher solvents.

Very new to this all apart from syringe filtering.
With glass can you get sterile filter membranes.

I presume with glass as well, filtering temp isnt such a worry and as you said harsher solvents.

Depends on your filter material. A vacuum filtration apparatus uses whatman filter circles so yes .22micron nylon filters are about 25 cents. You can still melt the filter, but the filtration setups really do work a lot better and the filter is at least supported by a particle type filter as well.

Depends on your filter material. A vacuum filtration apparatus is all glass and uses filter paper, I prefer nylon. You can still melt the nylon if you are super hot.

This...

You want to filter while it's still warm.. but let it cool back to room temperature before you distribute into your vials. Hot oil expands. You will come up short on your fill lines if you don't let it cool down to room temperature.